paranucleolus


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sex chro·ma·tin

a small condensed mass of the inactivated X-chromosome usually located just inside the nuclear membrane of the interphase nucleus; the number of sex chromatin bodies per nucleus is one less than the number of X-chromosomes; normal males and females with Turner syndrome (XO) have none (sex chromatin negative), normal females and males with Klinefelter syndrome (XXY) have one, and XXX-females have two. For technical reasons only about half the cells in a preparation show typical masses.
See also: Lyon hypothesis.
Synonym(s): Barr chromatin body

paranucleolus

(păr″ă-nū-klē′ō-lŭs)
A darkly staining structure within a cell nucleus.